One use for tables is to translate field values, or change one field value to another. You might want to do this if, for example:
Certain values are to be abbreviated.
A field is often misinterpreted because of punctuation.
You need the output data to have a uniform format.
You want certain field values to be replaced by spaces in the transfer file.
When a field value corresponds to a key value in the specified translation table, FORMS translates the field value to the corresponding value. If a field value is missing from the translation table or does not have a corresponding value in it in the Translation column, the value is not translated.
Using a translation table for a field is different from specifying a table for field validation. Using a translation table, a field value is translated to a corresponding value if it is found in the table, and no error status is set if it is not found. Using a validation table, the field is given an error status if it is not found in the table. You can specify the same table in each place to achieve both functions.
Normally, FORMS translates fields immediately after interpretation, which means that FORMS applies validation routines (if you specify any) to translated fields. This means that you can use tables to correct common format errors or uninterpretable punctuation marks or remove unnecessary digits before validation.
Example:
A mail order company has valid shirt sizes of even numbers from 36 to 44. But a customer, when ordering size 42 for example, might write 41/42, 41-42, 41, or some other variation. A translation table could be used to translate common variations to 42 before validation.
You can select Translate when transferred to change this, so that values are converted just before transfer, instead.
Translating or converting field values using a table (instructions)